MC9S12NE64_06 Datasheet, PDF (494/554 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 18 Debug Module (DBGV1)
least six addresses higher than address A (or B is lower than A) and there
are not changes of flow to put these in the queue at the same time, then this
operation should trigger properly.
18.4.2.5.4 Event-Only B (Store Data)
In the event-only B trigger mode, if the match condition for B is met, the B flag in DBGSC is set and a
trigger occurs. The event-only B trigger mode is considered a begin-trigger type and the BEGIN bit in
DBGC1 is ignored. Event-only B is incompatible with instruction tagging (TRGSEL = 1), and thus the
value of TRGSEL is ignored. Please refer to Section 18.4.2.7, “Storage Memory,” for more information.
This trigger mode is incompatible with the detail capture mode so the detail capture mode will have
priority. TRGSEL and BEGIN will not be ignored and this trigger mode will behave as if it were “B only”.
18.4.2.5.5 A then Event-Only B (Store Data)
In the A then event-only B trigger mode, the match condition for A must be met before the match condition
for B is compared, after the A match has occurred, a trigger occurs each time B matches. When the match
condition for A or B is met, the corresponding flag in DBGSC is set. The A then event-only B trigger mode
is considered a begin-trigger type and BEGIN in DBGC1 is ignored. TRGSEL in DBGC1 applies only to
the match condition for A. Please refer to Section 18.4.2.7, “Storage Memory,” for more information.
This trigger mode is incompatible with the detail capture mode so the detail capture mode will have
priority. TRGSEL and BEGIN will not be ignored and this trigger mode will be the same as A then B.
18.4.2.5.6 A and B (Full Mode)
In the A and B trigger mode, comparator A compares to the address bus and comparator B compares to
the data bus. In the A and B trigger mode, if the match condition for A and B happen on the same bus cycle,
both the A and B flags in the DBGSC register are set and a trigger occurs.
If TRGSEL = 1, only matches from comparator A are used to determine if the trigger condition is met and
comparator B matches are ignored. If TRGSEL = 0, full-word data matches on an odd address boundary
(misaligned access) do not work unless the access is to a RAM that manages misaligned accesses in a
single clock cycle (which is typical of RAM modules used in HCS12 MCUs).
18.4.2.5.7 A and Not B (Full Mode)
In the A and not B trigger mode, comparator A compares to the address bus and comparator B compares
to the data bus. In the A and not B trigger mode, if the match condition for A and not B happen on the same
bus cycle, both the A and B flags in DBGSC are set and a trigger occurs.
If TRGSEL = 1, only matches from comparator A are used to determine if the trigger condition is met and
comparator B matches are ignored. As described in Section 18.4.2.5.6, “A and B (Full Mode),” full-word
data compares on misaligned accesses will not match expected data (and thus will cause a trigger in this
mode) unless the access is to a RAM that manages misaligned accesses in a single clock cycle.
MC9S12NE64 Data Sheet, Rev. 1.1
494
Freescale Semiconductor